燃煤电厂脱硫废水零排放工程案例解析

Engineering case analysis of zero liquid discharge system of desulfurization wastewater in a Power Plant

近年来,燃煤电厂废水的“零排放”技术的研究与应用,有效解决了电厂高污染脱硫废水中硫化物、氟化物、悬浮物、重金属离子、COD等污染物对环境的严重污染。国电汉川电厂位于长江最大的支流汉江的下游,地处长江流域环境敏感区域,国电汉川电厂作为国内首批实践废水零排放的企业,建成了国内首个百万机组燃煤电厂零排放应用项目并实现平稳运行。开发的基于膜技术的零排放工艺路线成为目前应用最为稳定可靠的零排放技术。基于全膜法的废水零排放处理工程稳定运行2年期间,零排放系统的淡水回收率始终超过93%,同时实现了水、盐、泥的资源化回收利用,解决了当时淡水回收率低、产出杂盐副产物无法处置并存在二次污染风险等零排放技术的瓶颈问题。以汉川电厂零排放工程作为案例,从整体工艺、核心技术、运维管理及经济效益几个方面对汉川电厂的脱硫废水零排放工程进行解析,从工艺和经济角度总结汉川电厂脱硫废水零排放项目的成功经验,并探索未来废水零排放技术发展的可行之道。

In recent years,research work and application of power plant wastewater“Zero-Liquid-Discharge”have been carried out,which has been increasingly important and practical to solve the serious environmental pollution caused by pollutants such as sulfide,fluoride,suspended matter,heavy metal ions,and COD in the desulfurized wastewater of power plants.Guodian Hanchuan Power Plant is located in the downstream of the Hanjiang River,the largest tributary of the Yangtze River,wherein the environmentally sensitive area of the Yangtze River valley.As the first batch of domestic enterprises to implement zero wastewater discharge,Guodian Hanchuan Power Plant has built the first domestic zero-emission application of millions of unit generators power plant in China.Guodian Hanchuan Power Plant Desulfurization Wastewater Zero-Liquid-Discharge engineering project properly solved bottlenecks of Zero-Liquid-Discharge technology,like low water production rate,secondary polluted salt-mixture by-products,this project addressed Zero-Liquid-Discharge system for desulfurization wastewater advanced treatment based on the membrane methods.This project has been running stable for 2 years;the water production rate always exceeded 93%,and the recycling of water,salt and slurry were realized.In this paper,Zero-Liquid-Discharge case of Hanchuan Power Plant was analyzed from the aspects of process flow,core technology,operation,management and economic benefits,from which successful experience could be summarized for desulfurization wastewater treatment from the perspectives of process and cost;and looking forward to explore a promising way to develop Zero-Liquid-Discharge technology in the coming future.